For ease of referencing, here are the Bible verses relevant to its support of slavery.

The Old Testament
The Old Testament explicitly condones slavery -- providing instructions for acquisition, treatment and punishment of Hebrew and non-Hebrew slaves.

Exodus has Yahweh speaking to Moses directly, stating "Now these are the ordinances which you are to set before them" in Exodus 21:1 before a string of instructions including those pertaining to slavery.

Exodus 21:2-11
If you buy a Hebrew slave, he shall serve for six years; but on the seventh he shall go out as a free man without payment. If he comes alone, he shall go out alone; if he is the husband of a wife, then his wife shall go out with him. If his master gives him a wife, and she bears him sons or daughters, the wife and her children shall belong to her master, and he shall go out alone. But if the slave plainly says, ‘I love my master, my wife and my children; I will not go out as a free man,’ then his master shall bring him to God, then he shall bring him to the door or the doorpost. And his master shall pierce his ear with an awl; and he shall serve him permanently.

If a man sells his daughter as a female slave, she is not to go free as the male slaves do. If she is displeasing in the eyes of her master who designated her for himself, then he shall let her be redeemed. He does not have authority to sell her to a foreign people because of his unfairness to her. If he designates her for his son, he shall deal with her according to the custom of daughters. If he takes to himself another woman, he may not reduce her food, her clothing, or her conjugal rights. If he will not do these three things for her, then she shall go out for nothing, without payment of money.

That's a divine legal loophole for permanent slavery of your fellow Hebrew -- Marry your slave to another slave, blackmail him into permanent slavery if he wishes to stay with his spouse and children.

Exodus 21:20-21
If a man strikes his male or female slave with a rod and he dies at his hand, he shall be punished. If, however, he survives a day or two, no vengeance shall be taken; for he is his property.

Causing your slave to die after 1-2 days is criminal. But after 2-3 days is just dandy because he's just property anways.

Exodus 21:26-27
If a man strikes the eye of his male or female slave, and destroys it, he shall let him go free on account of his eye. And if he knocks out a tooth of his male or female slave, he shall let him go free on account of his tooth.

Beat your slave but don't cause permanent harm or you lose him/her.

Leviticus 19:20-22
Now if a man lies carnally with a woman who is a slave acquired for another man, but who has in no way been redeemed nor given her freedom, there shall be punishment; they shall not, however, be put to death, because she was not free. He shall bring his guilt offering to the LORD to the doorway of the tent of meeting, a ram for a guilt offering. The priest shall also make atonement for him with the ram of the guilt offering before the LORD for his sin which he has committed, and the sin which he has committed will be forgiven him.

If you fuck your slave, she has to be punished if she is betrothed to another man. You? Just go sacrifice a ram and you're scot-free.

Leviticus 25:44-46
As for your male and female slaves whom you may have—you may acquire male and female slaves from the pagan nations that are around you. Then, too, it is out of the sons of the sojourners who live as aliens among you that you may gain acquisition, and out of their families who are with you, whom they will have produced in your land; they also may become your possession. You may even bequeath them to your sons after you, to receive as a possession; you can use them as permanent slaves. But in respect to your countrymen, the sons of Israel, you shall not rule with severity over one another.

Hebrews for permanent slavery? No. Everyone else is game.

The New Testament
The New Testament is less explicit about slavery laws than the Old Testament. It recognizes that slavery exists but does not criticize it. Instead, it frequently compares slaves and masters to the relationship between believers and God, implying that it was acceptable.

Ephesians 6:5-9
Slaves, be obedient to those who are your masters according to the flesh, with fear and trembling, in the sincerity of your heart, as to Christ; not by way of eyeservice, as men-pleasers, but as slaves of Christ, doing the will of God from the heart. With good will render service, as to the Lord, and not to men, knowing that whatever good thing each one does, this he will receive back from the Lord, whether slave or free.

And masters, do the same things to them, and give up threatening, knowing that both their Master and yours is in heaven, and there is no partiality with Him.